The present invention relates to a circular external fixator.
As is known, an external fixator is an external orthopedic device that is fixed to the bone by virtue of metallic wires or pins, which pass through the skin and the soft tissues.
The Ilizarov fixator is a type of fixator having metallic rings that support the bone retention means, i.e., the wires.
A drawback of external circular fixators of the traditional type is that they require a laborious and relatively long assembly.
Another drawback is that the fastening systems and the structural components often constitute an obstruction and an obstacle for the placement of the wires.
Also, any repositioning or reconfiguration of the fixator during surgery is difficult and laborious.
Another problem of traditional systems resides in the difficulty encountered by the patient at home when he has to manually adjust the compression/distraction.
A further drawback of conventional systems is due to the presence of nuts or segments of bars that, particularly when located at the joints of the patient, always cause skin damage and possibly lacerations.
WO2008002992 discloses a radiolucent external fixation element with radio-opaque alignment structures used to form a plane orthogonal to the axis of the bone and center the fixation element upon the axis of the bone.
WO2011/060266 discloses a fixator system having an active strut that can be gradually or acutely adjusted. Adjustments can be made in six degrees of freedom. The passive struts can be rigidly locked or can be unlocked so as to be freely and acutely adjustable while gradual or acute adjustments are made using the one or more active struts.
WO0115611 discloses an orthopedic fixation device in which translation members are secured to adjacent tissue segments for reorientation relative to each other. The device includes telescopically adjustable struts that can be secured to base members by connectors that permit movement of the struts relative to the base members. Rotation of the struts is possible about three axes that intersect at a single coincident point of universal rotation.